Soil conditioner



United States; Patent Office Patented Dec. 11, 1958 SOIL CONDITIONER Richard C. Erwin, Mountain View, Calif assignor to Stauifer Chemical Company, a corporation of Delaware No Drawing. Application October 27 1954 Serial No. 465,149

7 Claims. (CL 47-58) This invention relates to certain soil conditioning compounds. So-called soil conditioners have been proposed in the past, but such conditioners have not been true soil conditioners but, in general, could be better characterized as soil stabilizers, since they maintain the soil substantially in the condition in which it is at the time the stabilizer is applied. In other words, such conditioners, to be effective, must be applied to soil when it is in a good condition of tilth, and such conditioners are very helpful in maintaining that condition. On the other hand, the compounds of the present invention are true soil conditioners inasmuch as they can be applied to soil in very poor physical condition and bring about a remarkable change in the physical condition.

Some of the soil conditioners which have been proposed in the past have also been applicable only to certain types of soil. Thus, such conditioners were not universal in application, but would prove advantageous in some types of soil and almost worthless in others. Further, such conditioners were not universally applicable to both acid and alkaline soils. By contrast, it has been found that the conditioners of the present invention are advantageous when used in any type of soil. Surprisingly enough, it has been found that the conditioners of the present invention tend to neutralize the soil so that the soil will have an ultimate pH of about 7 and this regardless of whether the original starting soil was acid or basic. Thus, the soil conditioner of the present invention tends to acidify basic soils and to alkalize acidic soils, so that the same preparation will render either a basic or an acid soil substantially neutral.

Certain soil conditioners which have been used in the past have also exerted a phytocidal action. Such compounds could not be used on lawn grass or shrubs or in any situation where roots were near the surface. Such conditioners were ordinarily used before the soil was planted, and then the soil permitted to stand for some time before a crop was planted therein. The soil conditioner of the present invention can be freely applied to growing crops or lawns and will not damage the crops.

Another unique feature of the soil conditioner of the present invention is that it releases carbon dioxide when water is appliedvto soil subsequent to the application of the soil conditioner. The liberated carbon dioxide bubbles through the soil and actually helps till the soil and renders the soil in better physical condition.

The use of the soil conditioner of the present invention is not to be confused with soil amendments based on ferrous sulfate, copperas, which has been the common and accepted source of iron; copperas is relatively poor in the places where the soil conditioner of the present invention is good. Because copperas has not been satis factory, its use for chlorosis has decreased and it is no longer used in the art for conditioning soils.

merated unique properties. The soil conditioner of the present invention is preferably made from a mixture of one part of ferric sulfate to three parts of calcium car bonate by weight although proportions as low as one part of ferric sulfate or as high as nine parts of calcium carbonate to equal parts of each may be used under certain conditions. Although it might be suspected that since these substances form gypsum, the efiect would be about the same as adding gypsum to the soil, the data herein submitted show that such is not the case and that an effect entirelydifierent from that of gypsum is obtained.

Another unique feature of the present invention is that the soil conditioner is completely non-irritating to the user, despite the fact that it contains a large percentage of ferric sulfate. When ferricsulfate is applied to soil, the dust has been found to be irritating to the user, while the composition of the present invention is not at all unpleasant to use.

In order todemonstrate the efiectiveness of the present invention, a number of tests were run using various soil types. The soil types selected were representative of widely contrasting soils and consisted of Hugo Clay Loam, an acidic soil having a normal pH of 5.5; Sorrento Learn, a substantially neutral soil having a pH of 7.1; and Alviso Clay, a very heavy alkaline soil having a pH of 8.5. In making the tests, soil was placed in flats having dimensions of 12" x 12" x 5". Each flat was filled with soil to a level of about 1" below the top. The soil conditioner was then raked into the top A" of soil, with a small implement, to simulate field tilling. A measured quantity of water was then applied to each flat in a manner comparable to field flooding. The flats were then set aside until the soil had dried to the proper moisture level for tilling. At this time, various measurements were made to determine the physical and chemical condition of the soil.

The soil was first tested for pH with the following results:

1 LIV-64 consists of one part ferric sulfate plus three parts calcium carbonate. This term MV-64" is a code number,

used by the applicant to designate this specific chemical composition.

The soil was also observed for signs of surface cracking, surface hardness, and ameasurement was made of the amount of force necessary to force a blunt instrument 3" into the soil. The following results were obtained.

Table II capillarity through the soil. Thus, this test was indicative, not only of the safety of the compounds under test,

I but also of the ability to aid the soil structure. ,One Prop ig series of pots was planted with radish, beet and bean r 6 seeds, and an application of MV-64 was then made over A 1 2 the surface of the soil at a rate equivalent to one ton Surface Cracking."- g g g of MV-64 per acre. In this test, there was a partial,

A 5 a 5 loss of bean seeds, but radish and beet seeds emerged sum Hardnesa.--. g g t '2 normally. The test was then repeated except that the Penetration lbs. A as 1.0 as 1.4 MV-64 was applied at the same rate and cultivated into toroeiorB" 3 g-g kg the soil just before planting. Under these conditions, there was a complete emergence of all seeds. The test was then repeated using the same amount of ferric suli r zir ti i fl liio rafa. fate over the soil prior to planting, but omitting the cal- B-Bssic soil-Alvlso Clay- I cium carbonate. Under these conditions, there. was a METHOD OF RATING 35% loss of beets, a 35% loss of radishes, and a 14% loss of beans. The test was then repeated except that Surface Cracking 5 m Force lgrg gg w no soil conditioning agent was used. Under these cono ditionst,h their; was 1E0. emergence of seeds whatsoever since e so waso such a poor nature that it would if Eli? if $1? i 1 giig'iil not permit sub-irrigation. 3. Moderate cracking. ggu 2 In another test, MV-64 was apphed to Sorrento Loam i1 y fi alising. sI'ver 'hsrn; Over4 .Very poor. soil at a rate of three tons per acre, and was placed 1 directly in furrows before planting Golden-Cross Bantam 4 (Corn. A similar test was made when an equivalent dos- :1: age of ferric sulfate alone was used. ,In the case of the application of MV-6 4, the top growth of the corn was increased, while the application of the ferric sulfate alone caused a decrease in growth.

The following tests show the effect of varying the proportions of ferric sulfate and calcium carbonate, as

well as the 9 0f gypsum: In still another test, MV-64 was applied at the rate Tmtment, M of three tons per acre to an established lawn of creep- No.1-Untnaa ing bent, Astoria bent blue grass and Bermuda grass t101bs.00 retest. mfl idhmmihw flf n and caused no in ury. Application of a ferric sulfate- No e-so CaC01+ No 5-15 caco1+2s i iil i liiiiifiilil'. peat moss mixture at. an equivalent rate caused almost it'. No, 0-50 CaflOi-l 50 0 Fe: 801); at 10 lbs. 100 sq. ft. Immediate blackin-g and burning of the bktdes and stems N 1 1 g -gm gil gg sg by mama! 5 of the grass. MV-64 was also applied to a new lawn c un Penen'atlm pH Add Neat. Acid Basic Neat. Acid Basto Neat. Acid Basic Neut.

5 5 5 5 a. s 10+ 2. 7 5. a s. 6 7. 1 i g s s 4 4 as 5.8 1. 5 as a 1 6.6 1 s 1 a a 2 1. o o. 9 0. a a s 7. 7 4. 9 5 s s 4 4 a 2. s 4. 1 1. 5 a 9 a 0 7. a 2 5 a a 4 a 1. 4 1. 9 1. a o. 1 7. a 1. o 2 5 2 a a 2 1. a 1. 9 0. 5 5. 5 a. 1 6. a -1-.- 5 5 10+ 0, 9 s 5 10+ In order to demonstrate the superiority of MV-64 of rye grass which was 1%" to 2" high, and caused be over gypsum, tests were run with Sorrento Loam. In injury thereto. the first test, gypsum was added at a rate equal to the The compounds of the present invention can be adgypsum formed by the application of MV-64 at the rate vantageously applied to soil at a rate of from one-half to of 10 pounds per 100 square feet and in the second, four tons per acre, and preferably at the rate of from one gypsum was added at the rate of 10 lbs./100 square to two tons per acre.

feet. The following results were obtained: The present invention depends upon an unexpected property of the stability of ground ferric sulfate. Ferric To 2 sulfate tends to take up water and cake or deliquesce in high humidity. It was thought that the presence of lime 0mm: 5 5 would adversely affect the stability of the ferric sulfate Hsrdnesi 5 3 and would react with it whereas the reverse is true; fig MV-64 cakes less and does not react in storage even though no precautions are taken to dry the product more It is apparent from the above tests that the soil coni c zig f commercial p ditioner of the present invention is capable of ncutralizing soil regardless of whether the soil is acid or basic. v A 8011 Realms agent comprising a COmblnallOn f It is fuither apparent that surface cracking is materially fmm 10 to Parts Of ferl'lc Sulfate and from 5 0 to 90 lessened by using the conditioner of the present inven- PM of calcium carbonate all Parts bung by Welghtfmess is also 2. As a soil treating agent, a combination of about 75 z a li ievg f I t i; is g iggar en t tli i gi gsum does not P I S by weight of calcium carbonate to 25 parts by achieve the same g weight of femc sulfate. I

Another series of tests was made to determine the f treating Q P S applying to safety of using th il diti f th present i the soil a soil treating agent contaimng from about 10 vention. In this series of tests, the soil was sub-irrito 50 parts of ferric sulfate and from 50 to 90 parts of gated by placing pots in a shallow pan of water so that calcium carbonate, all parts being by weight. it was necessary for the water to move upwardly by 4. The method of treating soll comprising applying to 2,77a,aao

6 the soil a mixture containing about 25 parts by weight of 1,428,633 Hotfman Sept. 12, 1922 ferric sulfate and about 75 parts by weight of calcium 2,625,529 Hedriclt Jan. 13, 1953 carbonate. 2,702,966 Boyd Mar. 1, 1955 5. The method of claim 3 wherein the compound is OTHER REFERENCES applied at the rate of from one-half to four tons per 5 3cm Chemical Abstracts, vol. 21, p. 4194 (1928), article The method of claim 3 wherein the compound is Reclamation of the Fresno Type Black Alkali Soil." applied at a rate of from one to two was per acre Mellor: A Comprehensive Treatise on Inorganic and The method of claim 3 wherein the compound is Theoretical Chemistry, pub. by Longmans, Green & Co.

worked into the top S01 10 (N. Y.), 1935, reprinted 1947, pp. 323-327.

Chemical Abstracts, vol. 37, col. 1542 (1943), article References Cited in the file of this patent lifectbtzf Limle in il g sz l 8 h Ch am et a tering i roperties wit emi- UNITED STATES PATENTS cals, Chemical and Engineering News, vol. 32, No. 6,

1,384,990 Campbell July 19, 1921 I pp. 488-492 (February 8, 1954). 

3. THE METHOD OF TREATING SOIL COMPRISING APPLYING TO THE SOIL A SOIL TREATING AGENT CONTAINING FROM ABOUT 10 TO 50 PARTS OF FERRIC SULFATE AND FROM 50 TO 90 PARTS OF CALCIUM CARBONATE, ALL PARTS BEING BY WEIGHT. 